Apparatus for cleaning root crops in the field

ABSTRACT

An apparatus for cleaning root crops while still in the field whereby the harvested crops are subjected to jet blasts of a cleaning agent without excessive dust generation.

BACKGROUND OF THE INVENTION

(1) Field to Which the Invention Relates

According to a first basic idea the invention relates to an installationfor the cleaning in the field of root crops, especially sugar-beets bymeans of jets of a cleaning agent hitting the beats on all sides afterlifting them off the ground.

A method with those generic features is known from the German publiclydistributed printed application No. 26 55 781 (DE-OS). With this knownmethod air is used as the cleaning agent. This known method producessatisfactory results for many applications. However, the high airconsumption may be disadvantageous, especially if important quantitiesof root crops must be cleaned as is the case e.g. with multi-shareharvesting equipment. An additional problem may be the control of thedust produced, particularly with dry soil.

(2) Short Outline of the Invention

Starting from these facts one basic problem solved by the presentinvention was to create an installation for a method as outlined above,having a high output of root crops to be cleaned combined with a highcleaning effect and avoiding the production of duct. An other basicproblem solved by the present invention was to make available a simpleand economic device for the performance of the method.

According to the present invention the solution of the first basicproblem consists of the use of a liquid as cleaning agent, preferablywater, at least in a preponderant part.

The liquid jets hitting the root crops to be cleaned are relatively hardand thus reliably able to loosen and to remove strongly adhering dirt.The liquid to be used makes it possible in an advantageous manner tosoak the root crops to be cleaned, thus facilitating the subsequent dirtremoval. The method according to the invention combines a great outputwith a relatively low cleaning liquid consumption. This allows in anadventageous way to proceed preferably with continuous jets. Thecleaning liquid, after having hit the root crops to be cleaned, washesaway in an advantageous manner the dirt removed, which not only avoidsdust practically right from the beginning but also guaranties anautomatic dirt evacuation. By collecting the dirt laden outgoingcleaning liquid and extraction of the dirt it is possible to to maintainthe cleaning liquid practically in a closed circuit with a relativelysmall loss. The water tanks or the like necessary to compensate thelosses therefore may be relatively small, which in an advantageous wayallows a most compact construction. Simultaneously it is possible in anadvantageous way to soak the root crops in the collected cleaning liquidthus performing a preliminary cleaning.

A preferred embodiment of the basic invention may consist of theproduction, at least partially, of the cleaning liquid by sapping of thevegetable products, e.g. the leafs which must be separated from theroots. This measure obviously is advantageous when cleaning beets sincethere is available a sufficient quantity of leaf and/or stalk materialand the like, having a relatively high water content which can besapped. As has been demonstrated by tests, the water produced by sappingin most cases covers the total needs. Therefore a reconditioning is notnecessary, which has an advantageous effect on the concept of thedevice. On the other hand these vegetable by-products and clippings aredehydrated, at least to a great extent, on the field thus representingpractically a durable or at least an easily preservable foddercontaining, as desirable, a great quantity of bulk. The usual silage ofbeet leafs and the like, often undesirable for environmental reasons,can be avoided in an advantageous way. This in turn avoids the muchfeared hyperacidity of the stomach of animals fed with silage products.

Other appropriate configurations of the installation for the methodaccording to the invention and advantageous measures for the productionof suitable devices for the performance of the method will result andwill be described with reference to the drawings in some examples ofexecution.

LIST OF FIGURES

FIG. 1 is a schematic representation of a beet harvesting device with abuilt-in liquid reconditioning installation,

FIG. 2 shows the detail of the liquid treatment installation by means ofa block diagramm,

FIG. 3 is a preferred embodiment of a liquid treatment installation withdirt removal,

FIG. 4 is another embodiment of a liquid treatment installation withdirt removal and

FIG. 5 is an embodiment with a sapping press.

DETAILED ACCOUNT OF WORKING EXAMPLES OF THE INVENTION

The beet harvesting machine represented in FIG. 1 is equipped in a knownmanner with cutting and lifting devices not specified in detail. Thebeheaded beets are introduced in an elevator 2 by means of the firstconveyor belt 1. Elevator 2 transfers them into a bunker 3. The beet'sheads mixed with leafs are collected by a second conveyor belt 4represented schematically and are also introduced into a bunker, eitherin the condition as harvested or in a condition to be described later orare simply disposed laterally to the harvesting machine. On their way toelevator 2 the harvested beets are hit by water jets which loosen andremove the ahderent soil. In the embodiment shown a cleaning station 6is passed through by a third conveyor belt 5 and is equipped with acircular arrangement of nozzles by means of which the beets to becleaned can be hit from all sides during their passage through thecleaning station 6. With the jets 7 working continuously, a highthroughput of the beets 8 laying on the conveyor belt 5 is possible andno control device is necessary.

As can be seen clearly from FIG. 2, the cleaning station 6 may consistof several cage-like annular conduits 9 having nozzles 10 at their innercircumference which are obtained simply by drilling. As can also be seenin FIG. 2 the third conveyor belt 5 may consist of a movable gridironthus allowing water to touch the beets from all sides and allowing thewater to flow away unrestricted. The embodiment of FIG. 1 shows aspilling pan 11 the bottom of which is inclined toward a dischargechannel 12. The used water carrying the dirt simply flows away to theground between the wheels on the side of the machine opposed to thecutting and lifting device. In order to obtain a reliable evacuation ofsettling dirt particles the spilling pan 11 and the discharge channel 12may be vibrated slightly by means of a vibrator 13. For the continuouswater supply to the nozzles 10, a high pressure pump 14, representedschematically in FIG. 2, is provided. The pump is connected to pressureline 15 which is connected by means of distribution lines 16 to theannular conduits 9, with the nozzles 10 being arranged cage-like side byside. The water reserve is contained in a tank 17 being mounted eitherdirectly on the beet harvesting machine or on the tractor. The intakeline 18 of the high pressure pump may be connected directly to the tank17 thus avoiding interruptions in the feeding.

For checking the filling level the tank 17 is equipped with glass gauges19. However, an automatic control gear can be conceived, giving alarm bymeans of a horn 20 or the like as soon as the water level falls short ofa given minimum. The water tank 17 will be filled either from time totime or permanently as will be explained in detail below. For thispurpose a filling socket 21 is provided.

The embodiment represented in FIG. 3 also shows the cleaning unit havinga tube-like housing containing at its inner circumference an encirclingarrangement of nozzles 10. The supply lines for the nozzles 10 may beintegrated in the housing which for this purpose may have a double shellarrangement. The tube-like housing of the cleaning unit 6 is inclined,and the lower end is directed against the direction of the motion of thethird conveyor belt 5, so that the used dirt-charged water flows awayfreely. This water may be evacuated laterally. In the embodimentrepresented the water flowing out of the tube-like housing of thecleaning unit 6 is introduced by means of a guide plate 22 into areservoir 23 located underneath the cleaning unit 6 in which the thirdconveyor belt 5 is passing. The beets to be cleaned are dumped in thereservoir 23 in which a sufficient quantity of water is maintained for abath as indicated by the reference mark 24. The third conveyor belt 5,dips into the reservoir 23 and is equipped with appropriate carriers 25each taking up one or several beets after a given stay-time in the bathand introducing them into the cleaning unit 6. The stay in the reservoir23 softens the dirt adhering to the beets which then can be easilyremoved by the water jets acting upon the beets in the cleaning unit 6.Simultaneously the reservoir 23 acts as a buffer for the cleaning unit 6allowing feeding a regular flow of beets to be cleaned into the cleaningunit 6, which is advantageous for efficiency.

If enough water is available the apparatus can be provided with anoverflow connected to a channel directed laterally. In order to allowfrom time to time the evacuation of the dirt deposited, an appropriatetrap may be arranged. However the reservoir 23 makes possible the use ofa closed water circuit thus diminishing the water consumption. In thiscase a quantity of water corresponding to the one coming from thecleaning unit 6 is taken from the reservoir 23 and is introduced into adirt collector. The solids thus collected may be dumped directly on theground. The treated water may be introduced into a tank 17 (FIG. 2) fromwhere the nozzles 10 may be fed.

The dirt collector may be a hydrocyclone fed with dirty water by meansof a low pressure pump mounted to the reservoir 23, the water outlet ofthe cyclone being connected directly or indirectly to a high pressurepump feeding the nozzles 10 the outlet for the solids opening directlyto the ground. The embodiment represented in FIG. 3 shows a multi-stepdirt separation. To remove dirt floating on the water level a spikedbelt or wheel 26 represented schematically is arranged to comb the watersurface in the zone of emersion of the third conveyor belt 5. The dirtsettling to the bottom of the reservoir 23 will be eliminated by anotherscuffling device. In the embodiment represented this device is a conicalscrew 27 ascendingly arranged in the reservoir 23. The drawing-in areaof the screw is a groove in the bottom of the reservoir 23 (notrepresented), while the upper part of the screw is located in a strainerhousing 28 which is partially above the water level. Thewater-dirt-mixture drawn from the bottom of the reservoir by the screw27 is squeezed due to the conical shape of the screw 27. The watersqueezed out can flow out of the pores 29 of the strainer housing 28 andcan return to the reservoir 23. In the embodiment represented thestrainer housing 28 is enveloped by a closed jacket 30 collecting thewater. The jacket 30 is equipped with an outlet socket 31 for thepre-cleaning water, which can be reached from the reservoir 23 only viathe strainer housing 28. If the pores 29 of the strainer housing 28 showa tendency to get plugged, this can be avoided by slight vibrations. Thenecessary vibrators 32 are represented schematically. The solids pressedout by the screw 27 are deposited onto another carrier arrangedtransversally to the screw. In the embodiment represented this carrieris a screw 33 dumping the solids to the ground aside the harvestingmachine. The water squeezed out by the screw 33 returns to the jacket 30of the screw 27 via the conduit 34.

To the outlet socket 31 of the jacket 30 is connected a low pressurepump 35 conveying the water drawn from the jacket 30 and thus indirectlyfrom the reservoir 23 to a fine separation unit. This unit may becomposed of one or several cyclones as mentioned above. In theembodiment represented this unit is a filtering unit 36, comprising adrum 37 into which the water coming from the low pressure pump 35 enterswithout counter-pressure. In drum 37 are arranged one above the othertwo filter plates 38 preferably having different mesh or pore sizes. Thedeposits on the filter plates 38 are removed by means of sweepers. Inthe embodiment represented the sweepers are composed of blades 40affixed to a vertical shaft 39. The solids removed are either directlydumped to the ground through a trap or, as represented in the presentembodiment, are deposited on a carrier 41 evacuating laterally. Thewater coming through the filter plates 38 flows into a water tank 17 asin FIG. 2. For this purpose a pump may be used which would be connectedwith the drum 37. In the example represented the drum 37 is sittingdirectly above the tank 17 to which may be connected the high pressurepump 14 feeding the water to the cleaning unit 6.

In the example represented in FIG. 3 the cleaning unit 6 is composed ofseveral, (in the present case of three) subsequent stages 6a, 6b, 6c.This allows for a multi-step treatment of the beets. In the last stage6c the beets previously treated with water jets may be dried. By meansof the pressure line 42 This stage may be connected to a source ofcompressed air not defined in detail. Both previous stages may beconnected to the high pressure pump 14. However, it is conceivable toproceed to a pre-cleaning in the first stage 6a with water takendirectly in the reservoir 23. Subsequently the cleaning operation isfinished in the following stage 6b using clean water coming from tank17. This clean water may be obtained by separation as shown in theexample represented or by another process described in detail below orbe simply poured into the tank 17 from an appropriate source.

The embodiment represented in FIG. 4 also represents a closed watercircuit. Basically the concept is identical to the one of FIG. 3.Therefore the explanation of identical items can be avoided. In thisembodiment the third conveyor belt 5 passing through the reservoir 23simultaneously removes the solids from the bottom of the reservoir. Forthis purpose the third conveyor belt 5 is arranged approximatelyparallel to the bottom and provided with sweeping components 43 whichmay be transversal reglets or the like. These sweeping components 43pass over a well 44 arranged transversally to the motion of the belt atthe upper edge of the reservoir. The solids removed from the bottom ofthe reservoir will fall into this well. The bottom of well 44 is achannel in which is arranged a screw 45 squeezing the solids containedin the channel and conveying them laterally to be dumped to the ground.The return conduit 46 connected to the housing of screw 45 may beconnected directly to the reservoir 23 or, as illustrated in theembodiment, may be a deviation of the pump intake connected to theoutlet socket 47 of the reservoir. The well 44 is located between thereservoir 23 and the cleaning unit 6. Therefore the dirt loaded watercoming from the cleaning unit flows into the well 44 via the guide plate22. In order to maintain a sufficient water level in the reservoir 23,at least the rear stages of the cleaning unit could be a double shellstructure, the inner shell being a strainer 48 bearing the nozzles 10.This component could be surrounded by a jacket 49 connected to thereservoir 23 by means of the pipe 50 by-passing the well 44.

The filter unit 36, fed by the low pressure pump 35 connected with theoutlet socket 47 of the reservoir 23, is in the present exampleintegrated in a water tank 17a supplying the water for the cleaning unit6. The water tank 17a is connected to the high pressure pump 14 feedingthe cleaning unit 6 in a parallel arrangement with the tank 17 providedto receive the water compensating the losses, the high pressure pumpbeing connectable alternatively with tank 17 or with water tank 17a.Preferably the valve 51 is controlled by a monitoring system located inthe water tank 17a in such a way that when falling short of a givenlevel tank 17, (being practically a reserve tank), is connected. In theexample represented in FIG. 4 the cleaning unit 6 is composed of twostages 6a and 6b arranged one behind the other. The second stage 6b isfed by the high pressure pump 14. The first stage 6a serving for thepre-cleaning is fed by a medium pressure pump 152 the intake of which isconnected to the water tank 17a.

In the preceding embodiments the losses of water which cannot be avoidedmust be compensated with water taken from an appropriate source. Inorder to avoid this a water recovery installation may be provided. Thiskind of installation may e.g. recover the water in the ambient air. Inthe embodiment represented in FIG. 5 water is recovered from the headsand leaves of the beets harvested, these parts being mainly composed ofwater. This water is not only sufficient to compensate the losses of aclosed circuit but covers the needs of an open circuit.

For this purpose a sap press 52 is represented in FIG. 5 which is fedwith the beet heads and leaves 8a by means of a second conveyor belt 4arranged after the cutting device. Preferably the sap press 52 ispreceded by a crushing device which in the present case is a stawcutting device 53. If a buffer tank is arranged after the sap press 52,the sap press may be operated intermittently. In the example representedthe sap press is working continuously. The sap press 52 is composed of ascrew 54 diminishing in diameter in feeding direction being located in astrainer housing 55 which in turn is surrounded by a jacket 56 having awater outlet 57. At the small end of screw 54 is provided aninterchangeable discharge nozzle being in the present case an apertureddisk 58.

This allows passing the solids to small pellets, or the like which aredirectly fed to animals or easily dried and thus preserved. In theexample represented a bucket 59 is provided for receiving the solids andwhich may be emptied from time to time into a truck placed alongside thefield.

If the filtering action of the strainer housing 55 is sufficient theoutlet 57 may be connected directly with a pump feeding the cleaningunit 6. In the example represented the water coming out of the sap press52 is transferred to a filter unit 36b integrated in a water tank 17b.If the water tank 17b cannot be arranged directly under the sap press 52as shown in FIG. 5, a low pressure pump 60 transfers the water comingout of the sap press to the water tank 17b containing the filter unit36b and being connected to the intake pipe of the pump feeding thecleaning unit. In the example represented a high pressure pump 14 isprovided followed by a throttle 61.

The preceding practical examples of the invention are not limiting. Acertain number of possibilities are available to the man in the art forthe adaption of the basic solution according to the invention to a givenspecific case.

The embodiments of the invention in which an exclusive privilege orproperty is claimed are as follows:
 1. An installation mounted on aharvester for cleaning root crops in the field by spraying jets of wateron all sides of the root crop after its removal from the soil,comprising:a cleaning unit mounted on the harvesting machine having aplurality of inwardly directed peripherally arranged jets for spraying acleaning liquid on all sides of the root crops to clean them; conveyormeans passing through said cleaning unit and permeable to the spray fromsaid jets, capable of transporting the root crops to be cleaned throughthe cleaning unit and depositing them after cleaning in a crop storagebunker; means for supplying cleaning liquid to the jets of said cleaningunit under pressure; means for collecting the cleaning liquid after ithas been sprayed to clean the crops; means for removing residues cleanedfrom the crops from the collected water; means for recycling saidresidue-removed water to the jets; and receiving device means forpre-soaking the root crops in cleaning liquid comprising: a conveyormeans for conveying the root crops from the ground to a pre-soakingreservoir containing cleaning liquid, and a conveyor means for conveyingthe root crops through said pre-soaking reservoir, wherein the receivingdevice is embodied by a reservoir (23) having an opening for theintroduction of the root crops and being located at a lower level thanthe cleaning unit (6) and in which passes the third conveyor belt (5)having carriers for the root crops to be cleaned, the cleaning unit (6)being a strainer (48) having nozzles (10) and being enveloped by ajacket (49) the interior of which can be emptied into the reservoir(23).
 2. An installation according to claim 1, wherein the outlet socket(31 respectively 47) of the reservoir (23) is connected to a lowpressure pump (35) feeding into a filtering unit (36) comprising a drum(37) in which at least one filter plate (38) is arranged to whichbelongs a blade (40) for the removal of the solids, a tank (17respectively 17a) for the liquid being installed behind the filter unit(36) and a high pressure pump (14) or a medium pressure pump (152)aspirating liquid from the tank to feed it to the cleaning unit (6) andwherein at least one scraping device (26 respectively 27, respectively5, respectively 43) having carriers collecting the dirt residues isprovided.
 3. An installation according to claim 2, wherein the scrapingdevice is a screw (27) having a diameter diminishing in the feedingdirection and being arranged ascendingly being equipped with a vibratingdevice, the intake side of which being located in a channel on thebottom of the reservoir (23), the upper part being borne in a strainerhousing (28) situated above the water level (24), said strainer housingbeing externally enveloped by a jacket (30) having an outlet socket(31).
 4. An installation according to one of claims 1, 2, or 3 whereinin the zone of emersion of the conveyor belt (5) is arranged a spikedbelt or wheel (26) having spikes penetrating in the liquid and movingperpendicularly to the motion of the conveyor belt (5).
 5. Aninstallation according to one of claim 1, 2, or 3, wherein a top andleaf conveying device (4) being embodied preferably as a straw cuttingdevice working continuously feeds the vegetable products cut off fromthe crops after harvesting into a sap press (52) having at the outletside an interchangeable discharge nozzle (58) for the pressed-outmaterial, said sap press being followed by a filter unit (36b).
 6. Aninstallation according to claim 5, wherein the sap press (52) isembodied by a screw (54) having a cross section diminishing in feeddirection and being borne in a strainer housing (55), said strainerhousing being enveloped by a jacket (56) closed externally and having anoutlet (57).
 7. An installation according to claim 1, wherein thecleaning unit (6) comprises several subsequent stages (6a respectively6b, respectively 6c) and the intermediate stage (6b) being supplied withwater from a high pressure pump (14) the liquid having comparably thehighest cleaning efficiency and the last stage (6c) seen in the feedingdirection of the conveying component (5) is connected to a compressedair line (42).